threading in java: part 2

import java.util.*;
import javax.mail.*;
import javax.mail.internet.*;
import java.io.*;

public class ThreadExample {
    private static class WorkerThread extends Thread {
        javax.mail.internet.MimeMessage message;
        public WorkerThread(String body) {
            Properties properties = System.getProperties();
            properties.setProperty("mail.smtp.host","127.0.0.1");
            properties.setProperty("mail.smtp.port", "2025");
            Session session = Session.getDefaultInstance(properties);
            message = new MimeMessage(session);
            message.setFrom(new InternetAddress("[email protected]"));
            message.setRecipients(Message.RecipientType.TO, "[email protected]");
            message.setSubject("Greetings");
            message.setText(body);
        }
        public void run() {
            try {
                for (int i = 0; i < 1000; i++){
                    Transport.send(message);
                }
            } catch (Exception e) {
                System.out.println("Failed sending message");
            }
        }
    }

    public static void main(String[] args) throws Exception {
        File foo = new File("foo1");
        String body = getContents(foo);

        WorkerThread[] threads = new WorkerThread[100];
        for (int i=0; i < 100; i++) {
            threads[i] = new WorkerThread(body);
            threads[i].start();
        }
        try {
            for (int j=0; j < 100; j++) {
                threads[j].join();
            }
        } catch (InterruptedException e) {
            System.out.println("Threading Error");
        }
    }

    public static String getContents(File aFile) {
        //...checks on aFile are elided                                                                                                           
        StringBuilder contents = new StringBuilder();
        try {
            //use buffering, reading one line at a time                                                                                           
            //FileReader always assumes default encoding is OK!                                                                                   
            BufferedReader input =  new BufferedReader(new FileReader(aFile));
            try {
                String line = null; //not declared within while loop                                                                              
                /*                                                                                                                                
                 * readLine is a bit quirky :                                                                                                     
                 * it returns the content of a line MINUS the newline.                                                                            
                 * it returns null only for the END of the stream.                                                                                
                 * it returns an empty String if two newlines appear in a row.                                                                    
                 */
                while (( line = input.readLine()) != null){
                    contents.append(line);
                    contents.append(System.getProperty("line.separator"));
                }
            }
            finally {
                input.close();
            }
        }
        catch (IOException ex){
            ex.printStackTrace();
        }
        return contents.toString();
    }
}